Measurement of the ~0.1- to > 10-keV energy distribution for an argon Z-pinch at the 15-MA level

We report an approximate energy distribution (coarse spectrum) over the range ~0.1 to > 10 keV for the X-ray output of an argon Z-pinch. The tests, conducted at ~15-MA peak current, utilized an 8-cm diameter double-shell nozzle. Sze et al. (2001) have previously described the performance of this Z-pinch with emphasis on the K-shell line emission at ~3 keV. Additional measurements that address the non-K-line output of the Z-pinches are presented here. On the one hand, > 4-keV photons due to the free-bound continuum constitute a significant fraction, almost 30%, of the nominal K-shell emission. On the other hand, the sub-3-keV L-shell lines and continuum show distinctive time histories and significant yields. These nonresonance-line emissions are important for a more complete understanding of the implosion physics, for proper analysis of diagnostic responses, and for their effects upon objects exposed to the Z-pinch's radiation. Index Terms--X-ray diagnostics, X-ray spectra, Z-pinches.